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["puestadelsol83" <address@concealed>]

Hi!
I read something in the guide about s/mime and encryption in sympa.
If I have a user in ldap tree that is a member of a list in sympa and this 
user want to send an enctypted message. The certificate that he use is the 
same that he use in his ldap tree or is necessary to create a new certificate 
that is visible only in sympa?If it is the same is necessary to include the 
certificate in the apposit directory in sympa?
sorry but this is the first time I use certificate.
Thanks